The frontal eye fields of the cerebral cortex contain neurons which discharge before saccadic eye movements. Previous work from this laboratory has shown that the region of the frontal eye fields with presaccadic cells projects to the superior colliculus in an orderly fashion. Electrical stimulation of the superior colliculus excites presaccadic neurons in the frontal eye fields antidromically. Electrical stimulation of superior colliculus regions participating in the genesis of saccades greater than 10 degrees results in saccades whose amplitude and direction are affected by the orbital position of the eye. Stimulation of the superior colliculus also results in head movements whose parameters are affected by gaze position. The saccades evoked by electrical stimulation of the superior colliculus from identical orbital positions can be affected by the position of the animal's head relative to the midline of the body.